


A Perfect Wedding

by BubblyShip



Category: Undertale (Video Game)
Genre: Anxious Alphys, Bad mom, Everyone Is Gay, F/F, Homophobia, M/M, Mommy Issues, Pranks, Protective Sans (Undertale), Protective Undyne, Supportive Sans, Wedding Fluff, Wedding Planning, Weddings, alphdyne wedding, toxic mom
Language: English
Status: Completed
Published: 2020-04-22
Updated: 2020-04-22
Packaged: 2021-03-02 02:07:01
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 4,354
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/23787547
Author URL: https://archiveofourown.org/users/BubblyShip/pseuds/BubblyShip
Summary: It’s time for Alphys and Undyne’s wedding! Hooray!Except for one of the brides Moms is not supportive of their lesbian relationship, and Sans is too good of a friend to Alphys to let her Mom treat her that way.With some Sansgore in the background, of course.
Relationships: Alphys/Undyne (Undertale), Asgore Dreemurr/Sans
Comments: 16
Kudos: 116





	A Perfect Wedding

He felt those “karen” vibes the moment she walked in. The way she wore herself high, and her snide remark was all he needed to know that she would be a problem.

“So this is the girl,” She had spoken with a tone that sounded displeased, tilting her snout up with annoyance.

Oh, it was so  _ on _ .

Alphys was his, hands down, best friend. When he was asked who his friend was, she was the first person that Sans would speak of without any hesitation. They had a long history together, they were extremely close. Alphys and Sans often had anime nights, often binged on food, and were good friends. Naturally, due to their close friendship, she told him about her Mother.

And by the lord Toby Fox himself, she was worse in person. Alphys had not described her bad enough.

“Yes ma’am, I’m Undyne, your daughters fiance,” Undyne had replied, sticking out her hand to shake. “I’m Captain of the Royal Guard and I personally train under Asgore, I ensure you your daughter is in safe hands, she’ll be protected and secured financially.”

Undyne wanted to impress her, after all she would be her Mother in law. It was her only chance to have a Mother, as hers had died when she was younger. Gerson was accepting of Alphys thankfully, and was amazingly supportive during this. 

Which only made Alphys’ Mom stick out more.

“Why did you settle for someone training under Asgore instead of getting Asgore himself?” Her Mother had asked, turning to Alphys.

The woman hadn’t even taken off her shoes yet and was insulting Undyne, telling Alphys to aim higher for the King himself. The King who, if the woman had taken the time to step inside and see their house, was sitting at the kitchen counter and holding Sans’ hand. Who was also gay, like her daughter. 

“Because… u-um… I like Undyne!” Alphys stuttered, “She’s very nice a-and I like her a-a lot, you’ll like h-her too!”

“We’ll see.”

Since Sans was dating Asgore, he was often involved in Frisk’s life, especially with their school problems. It was an odd situation, where Frisk would transfer between Asgore and Toriel, which caused Sans to become their ‘Duncle’. And being the Duncle, he was the only one able to handle the school conferences, causing him to encounter plenty of entitled Mothers who reminded him of Alphys’ Mom. 

But, hey, Sans was a forgiving guy! Well, no, he wasn’t. When Sans hated someone, he  _ hated  _ them. But what Sans did was give people chances to prove him wrong. Chances to be decent people. So he didn’t say any mean or snide comments when her Mom came into the room, he even shook her hand and introduced himself as Asgore’s boyfriend. 

They were supposed to have dinner with the woman, Undyne wanted to try to make a relationship work. To Undyne’s credit, the girl was trying. She had brushed her hair that morning, took two showers, and even forced herself into a dress even though she despised them. Alphys had even wore some lipstick, even though Sans knew she hated makeup and that it made her skin itch. Undyne didn’t mind makeup at least, but she hated how restraining dresses were. How it would hug her chest uncomfortably and be too loose on the bottom, she preferred jeans and t-shirts. Heck, even Papyrus had wrestled Sans into something nicer. Everyone was trying their best to make this work.

Toriel had went all out for their dinner. With the light of the even practically sparkling her meal, she had presented it. Several steaks, chicken, turkey, rolls, green beans, mashed potatoes, and several different types of pies. Sans knew she had been up since six cooking everything, and she had done the math for each meal to make sure everything would be warm when the woman arrived.    


If she had been on time, it would have been warm. She was almost an hour late, having texted Alphys excuses about traffic. Sans saw the receipt for fast food sticking out of her purse, she had went out to a restaurant before she came here. The woman never had any intentions of eating Toriel’s food. 

It wasn’t like she had been caught off guard, they had been planning this for over a week. The woman knew full well that Toriel would be serving dinner, and still went out for food. 

“I’m good,” She had said when Toriel offered her some food, “I don’t eat food from fur based monsters. You might have shed inside of it.”

No, she didn’t. Not only did Sans watch her cook the meal, he also lived with a fluffball of his own. Shedding into food was never a problem, especially with the precautions Toriel took. She made sure to wear gloves, she kept her ears back, even wore long sleeved shirts to ensure no hair would get in. 

“Don’t worry, I take precautions, it’s hair free,” Toriel insisted.

“I’d rather not.”

Strike one. The woman never knew Toriel was a goat monster until she arrived, she had eaten the food just because she didn’t trust any of them. Then she went and refused to eat Toriel’s cooking. 

“So, um, Mrs. Code,” Undyne said slowly, “Your purse looks very nice! Where did you get it from?”

Sans noticed the impatient and awkward tapping of Undyne’s fingers against the table. Undyne hated talking about this kind of stuff, especially when it came to purses. She liked to talk about her fighting, or about anime, she liked to bond with people through their personalities. Not through their clothing. She was swallowing down her pride to try and bond with the woman, and this woman wasn’t bothering to try.

“I would tell you the store dear, but I don’t think you’d know of it,” She said, “Your dress is rather… tacky.”

“Oh, is it? I’m sorry about that?” Undyne bit down whatever comment she had and gave a toothy smile.

“I-I picked it o-out…” Alphys whispered, awkwardly playing with her food.

“Why don’t you marry a man?” Mrs. Font had asked, “So you can have children. All woman should have children.”

“While I do love children, I do believe it is up to the female if she wishes to have a child or not,” Toriel had said, reaching out to rub Frisk’s head. “Alphys could always adopt if she and Undyne want a child.”

“But sorry ma’am, I don’t think we’ll ever be having any children,” Undyne said, “We help take care of Frisk, and since we both have Royal responsibilities, it wouldn’t be the best place to raise a child.”

“A woman's purpose is to have children, so quit your job and find a man, don’t waste your reproductive system just for a stupid science job.” Mrs. Code jabbed a pointed finger at her daughter. 

Strike two, and three, and just all of the strikes. That single comment alone had Sans staring at her like an idiot. Alphys had mentioned how terrible her Mother was, but gosh the woman was just terrible in person.

Asgore was the King, but the guy was too nice to even do anything about her. Guess that would explain why he ended up hooking with Sans and Toriel, as they were more firm people. 

“Alphys is real smart, and she likes science, along with Undyne. I think this arrangement is actually really good for her,” Sans said, “And she works directly with the King, so you know, it’s a really good position.”

“And if Alphys doesn’t feel comfortable having children, it’s her right not to,” Toriel agreed.

“But don’t worry about it, Mrs. Code,” Undyne said, keeping her voice from straining with anger. “We both have high paying jobs, and I’ll be sure to take care of Alphys. You don’t have to worry about her.”

“I’m worried about no one carrying on the family name,” She said, “And that Alphys will be marrying another woman, disgusting honestly.”

The rest of the dinner went about the same. Her comments were quick, not only insulting Undyne and Alphys, but everyone else. Asgore was the only one she really stepped back from, along with Sans, as he was literally holding the Kings hand the entire time on the table. 

Which meant Sans had full access to prank her, and for her to not pay attention to him.

Sans had expected her to drop the wedding, but the woman did agree to attend. Why wouldn’t she, it was an event full of expensive free food and social conversation. Of course, she agreed with a snide comment about how Alphys would have to dress shop again since she likely gained weight, according to her Mother who had never visited in the past few years.

The second the door closed, Undyne snapped. She slammed her hand against the wall and leaned against it, baring her sharp teeth that Mrs. Code had said were “more yellow than her nonreligious daughter”. 

“I can’t stand that woman!” Undyne snarled, “Who does she think she is, insulting you that way?”

“I see what you meant when you said she is an actual b*tch,” Sans muttered.

“It’s f-fine, it’s just m-my Mom,” Alphys said, “She’ll just c-c-come to the wedding, then she’ll be gone.”

“Are you sure you want to invite her there?” Toriel asked Alphys, “I know she is your family, but she is rather toxic to you.”

“I’m never going to call that woman my Mother in law,” Undyne muttered, “It’s fine for people to insult me, I don’t care. But no one insults Alphys.”

“It’s okay, w-we never have to t-t-talk after the wedding,” Alphys said, “I don’t like her m-much either, but s-she’s family! I can’t just l-leave her out!”

“Well, I mean, you can,” Sans pointed out, “Just because she’s blood related doesn’t mean she’s your true family. I’d rather not see her at the wedding, she might ruin it.”

The thing about Alphys was that she was too forgiving. Despite how her Mother not only treated her, but her friends and fiance, she begrudgingly decided to keep her Mom on the guest list when she was guilted into it over text. 

It was pretty obvious for everything the woman was going to ruin the wedding. Just being in the same room as her was a nightmare, she made everything about herself and judged everyone else. 

Despite the hanging doom, Alphys and Undyne continued their planning for the wedding. Sans helped, as he was one of the groomsmen, and the brother of the best man. Of course he was going to help, they were both his friends. Slowly, but surely, it all came together. Things were bought, suits and dresses were fixed, everything was good.

“Sans…” Asgore had slurred, sleepily blinking as he hugged Sans’ waist from the side. “Go to bed.”

“I will, sorry.” Sans shut his computer, sighing as he placed it onto the nightstand. 

“You’ve been up the past few nights, everything okay?” Asgore asked, still sleepy as before. “Your not worried about the wedding, are you? It’s going to turn out okay, even if her Mom does show up.”

“I know, I’ve been working on that,” Sans said as he slid under the covers.

At least Alphys and Undyne were still excited about the wedding, that was what really mattered. They were adorably in love, and they both really deserved this. Alphys was so giggly at her party that she was practically bouncing in her seat from excitement. They both were great people, and both deserved to be in love.

Which is why Sans couldn’t let her Mom ruin this. 

On her wedding day, Alphys was extremely giddy. She was a constant blushing mess, but between Sans, Bratty, and Catty, they all managed to settle her down and help keep her excited instead of nervous with a bit of help from Mettaton. Her dress looked amazing, and Alphys had done a funny pose with her hands in the side of her dress to show it had pockets (that was her favorite part of it, she wanted to show Undyne so badly) and, honestly, was pulling off white really good. White was a good color that went with her skin tone.

Unfortunately, her Mom also had the same skin tone and also knew white looked good with it. So she had worn white to the wedding. To a wedding where Alphys and Undyne specifically told everyone not to wear white for the two brides.

Bratty and Catty had been doing Alphys’ makeup when her Mom had knocked on the door for the room, and Sans almost punched her when he saw her dress. Seriously? She was going to take her own daughters wedding from her, too?

Sans didn’t even hold back when he opened up the door. “You weren’t supposed to wear white, only the brides do.”

“Oh my, I must have forgotten,” She had hummed out, checking her nails. “But it does match my skin, don’t you say?”

Sans didn’t reply, looking at her. He really hated her guts right now. He knew she had given him and Undyne side looks during the dinner just because she was lesbian and he was gay, and he knew she only kept her mouth shut about him because he was dating the King and she couldn’t insult him. 

No doubt Alphys would be upset if she saw her Mom wearing white, and no doubt just her being there would ruin her happy vibe. 

“Um, I think it’s a bit weird you came to see Undyne getting ready,” Sans said, blocking the view to pretend that Undyne was the one in the room, not Alphys. “You finally came around to her being your daughters wife, then? That’s accepting of you!”

“I came to ask Alphys where the drinks are, I don’t care about her wife,” Mrs. Code had said.

She had told him her first name before. He just hadn’t cared.

“The drinks aren’t going to be pulled out until after they get married, during the reception,” Sans explained.

“I’m her Mother, I can have some wine earlier,” She said.

“Don’t care,” Sans said blankly.

“What do you mean you don’t care? This is my daughters wedding, I should get some drinks before anyone else, I don’t want them to drink all of the red wine,” She said.

“Fine, come on.”

He knew arguing with her wasn’t going to work, and he knew that pictures were going to be happening soon. If this woman got into their wedding photos, they’d always be forced to remember that she practically upstaged Alphys just to try to look prettier than her. 

The bar had been in the back, and when Sans had reached it he went around the counter, grabbing one of the bottles of red wine from under the counter. “Here’s the wine.”

“Oh, finally,” Alphys’ Mom had said, settling down at the counter. “If she’s wasting my time driving out here to see her destroy gods name by getting married to another woman, I should at least have some wine. My big day was ruined by-”

Sans cut her off by flipping the wine bottle over as soon as he opened it onto her lap, effectively ruining her white dress in one fell swoop.

“What the hell?” She had screeched, jumping back out of her chair with disgust.

“There, you have less white on you now,” Sans said casually, tipping the wine bottle back so he could take a sip from it. “Your lucky Alphys and Undyne don’t like red wine, they both prefer white if they had to choose. They won’t miss it.”

“You ruined my dress, you idiotic gay skeleton!” She yelled, rubbing at the stain.

“Yeah, a skeleton who’s gay for the King of monsters, and the skeleton who also helped pay for this wedding and does have the authority from both of the brides to kick you out,” Sans said, pointing the top of the bottle at her. “I can pay for it, I used to be a scientist, I got a lot of cash myself, I wouldn’t trouble the King of monsters to do it. Unless, of course, you’d like to go bring up with him how you were being homophobic to his best fighter and best scientist?”

The woman was left standing there for a moment before she exhaled sharply, turning flat on her heels and storming out with the intentions to change, muttering she would “be back”. 

Yeah, Sans was counting on it. He had spent a few weeks planning all of this, why let it go to waste? Alphys wanted her Mom to be there to include her family without feeling guilty, so her Mom was going to be there. She just wasn’t going to be happy while she was going to be there, and by no ways was Sans going to let her steal Alphys’ day from her.

“Sans, what are you planning?”

There was Asgore, leaning against the doorway on the other side of the room, where neither Sans nor Mrs. Code had noticed him. 

“How’s Undyne doing?” Sans asked, changing the subject as he pulled out two wine cups from under the counter. 

“Sans, Alphys’ Mom just ran out with wine on her  _ white  _ dress,” Asgore pointed out, approaching his boyfriend. 

“You got a problem with that?”

“No, I can pay for it if she complains,” Asgore said, “Undyne is freaking out right now, she doesn’t want Mrs. Code to ruin the wedding.”

“And she won’t.”

Sans quickly poured two cups of red wine for them, pushing one to Asgore.

“We aren’t supposed to be drinking before the ceremony,” Asgore pointed out.

“The woman loves red wine,” Sans pointed out, lifting up his own glass. “She made that pretty clear. It would be a shame if there was only enough for everyone else, and that she didn’t get any.”

Asgore chuckled when he caught ahold of Sans’ scheme, reaching over to grab his glass. “You’ve been planning a prank on her, haven’t you?”

Sans clinked his glass against Asgore’s. “You know me too well.”

~~~~~~

“Do you, Undyne Fish, take Alphys Code as your…”

Sans looked over the large crowd, noticing Alphys’ Mom, giving her a smug look. He then turned his attention to the pair, both of which were practically glowing from their excitement.

“Hell yes!” Undyne roared.

“Then you may now kiss-”

The priest didn’t even get the rest of his sentence out before Alphys was lunging up to kiss her girlfriend, Undyne quickly joining in with a bear hug, practically picking up her girlfriend. The room broke out into applause, Sans not holding back as he furiously clapped. Though, his clapping was nothing to Papyrus’, who clapped so fast his hands were practically blurs. Catty and Bratty were jumping up and down, while a few of the dog monsters started o bark from their excitement. Mettaton broke down and practically sobbed in the corner, dabbing the edges of his eyes as he started to short circuit. 

“Darling you look so precious!” Mettaton wailed.

As expected, the ceremony was beautiful and perfect. Both of the girls looked amazing, and were both extremely happy. Everyone was cheering and clapping; it was perfect. 

Sans took another look at Mrs. Code, glad that he had  _ convinced  _ her to change her attire into a green dress she must have pulled out of her closet. Sans was actually willing to give mercy to her if she had just held back her tongue, but she hadn’t, and insulted Alphys. And he knew she would keep doing that, that the woman didn’t care about the wedding. It wasn’t her day, though, it was Alphys’ and Undyne’s. 

And darn it, Sans was going to make sure it went perfectly. Even if he had to chase out Alphys’ homophobic Mom with a flaming torch.

Soon after, the reception started, with people dancing in the middle of the room. Food started to be plated, along with drinks being served. When Mrs. Code had finally arrived at the bar, she had learned that all of the red wine was gone. She looked at Alphys’ head table to find Sans drinking the last cup of red wine, giving her a small, taunting wave. 

Sans’ speech was pretty short and filled with puns, but he made sure to give another reference to the red wine by raising it, declaring he drunk most of it to ensure Alphys wouldn't have to drink a flavor she hated before giving cheers. Of course he only kept that part small, and went back to talking about Alphys and Undyne. Because they deserved the attention. 

Oh, that was only the start of it. 

Sans was at the head table, between Papyrus and Asgore, so he had the entire view of the room as one by one, his pranks went off.

The first mistake Mrs. Code had made was thinking she could trust the carmel apples. On the table was a combination of normal covered apples, but there was one extragogent one, which he had spent at least an hour decorating. Everyone else, being good people, left it there as they thought it would be for Alphys or Undyne. Mrs. Code took it, thinking it was a delicious treat. 

It was a caramel covered onion. 

Sans didn’t want to accidentally hit anyone else with his pranks, so everything else had to be ensured that only she would trigger them. Which required some participation from his part. Sans usually was lazy, but for Alphys, he was willing to do this. 

The funny thing about the wedding was that Sans was the one who hired most of the people working there. Which meant he was their boss for that event. He had given them their instructions while Undyne and Alphys were still getting ready, which gave them time to prepare.

Did Mrs. Code want a drink? The bartender would always be out of red wine, and would serve her lukewarm, watered down drinks with a pinch, or handful, of salt thrown in. The taste should counteract her onion.

Not that Sans would let these people go down without stepping in. She no doubt demanded to get a new drink, insisting it was filled with salt.

“Is there any problems here?” Sans had asked, walking up with his hands in his pockets. 

“Can I see the person who hired you for this wedding?” She asked the bartender.

“That would be me,” Sans answered, “Is there a problem with your drink?”

“It’s salty.”

Sans grabbed her cup, gently pouring a minimal amount into another cup. He took a sip of it, and would have gagged if he could. The salt was definitely there.

“I think your mistaken, it tastes fine to me,” Sans said, handing her own cup back to her.

When she had turned, he gave the bartender a thumbs up.

The rest of the night continued like that, Sans giving her the worst day of her life while Alphys had the happiest. This was due for awhile, really. He heard so many stories about this woman. How she had left Alphys at school and forgot to pick her up, forcing the lizard to trudge on an hour walk to get home. How she had ruined Alphys’ science project for a competition by spilling wine on it. How she had practically ignored Alphys ever since she had come out. Sans knew each and every story, and was prepared to avenge his friend and get her justice.

Prank after prank continued, slowly driving the woman insane. It wasn’t just that, though, he purposely made sure to drag the attention from her. She wanted to talk to the dogs? There was a squirrel outside that needed to be chased away so it wouldn’t scare Alphys. She wanted to talk to Grillby? Sans asked him if he had a chance to go congratulate Alphys personally, to which the fire monster scurried away with a low “thanks” to Sans. Only later did Sans catch on that she was trying to get into bed with him. Poor fellow.

He could see Mrs. Code slowly getting more red-faced over the course of the day, getting angrier and angrier over each prank. Until finally, she snapped.

“YOU!” She had screeched at Sans.

The woman stormed in, red jello sticking to her body. Maybe Sans might have given Frisk a crisp ten dollar bill to pull a lever if a certain person stood below the bucket, maybe he didn’t. 

“YOU DID THIS TO ME!” She had yelled, slamming her hands onto the table.

Everyone had fallen silent from her screams, the woman breathing heavily with a fuming nose and beat red face that matched the dessert now decorating her body. Sans gently took another scoop out of his red jello cup, eating a spoonful.

“Why do you think I did this?” Sans asked, voice muffled. “Could’a been anyone.”

She was fuming, almost like she was about to explode. Some people were snickering, a few of the clever ones had caught on to what Sans was eating and giggled. Alphys didn’t have any jello for the wedding, so it was obvious to connect Sans to the crime. But Mrs. Code was not a clever person, especially when she was angry. 

“ACK!” She screeched, turning around and storming out when her words had fallen flat.

“That explains the shipment of four crates of jello,” Asgore muttered lightly as the doors to the room were slammed open, then closed as she left.

Undyne lost her composure over the situation, she had lost it the moment the woman had stepped into the room looking like she did. Undyne bent over, slamming her hands into the table as she cackled with laughter. Alphys was covering her mouth, trying to suppress her giggles. She looked really happy. Even Papyrus, who usually hated Sans’ pranks, was snickering into his hand like Toriel was.

“Now this is the best wedding ever!” Undyne laughed, throwing her head back. “Hell yeah!”

“To a perfect wedding,” Sans chuckled, holding up his cup of white wine.


End file.
